1. Field of the Invention
The invention is generally related to the area of optical communications. In particular, the present invention is related to solder-free packaging method for integrated fiber optics device and parts using the method.
2. The Background of Related Art
Generally, an opto-electronic integrated device includes an optical part integrated with an opto-electrical conversion device. The optical part can be a WDM (wavelength division multiplexing) device, an optical collimating or focusing optics, or an optical taping device that splits a small portion of the total input signal to an alternative optical path for monitoring the intensity and wavelength changes of the transmitted signal. The opto-electrical conversion device can be either a photodiode or a laser diode. The optical part and the opto-electrical conversion device are generally sealed in what is commonly referred to as a TO-can. A TO-can packaging of an opto-electrical conversion device includes a metallic case with a transmission window or opening on top for transmitting or receiving optical signals.
An exemplary traditional packaging approach of an integrated device 100 is illustrated in FIG. 1. The integrated device 100 includes various components such as an optical device 103 and an opto-electrical conversion device in a TO-can package 102. The optical device 103 generally includes a plurality of optical subcomponents that are preferably aligned and fixed relative to each other and mounted inside a piece of gold plated tubing by thermal curing epoxy. The individual devices 102 and 103 to be integrated are then aligned and fixed relative to each other. Traditionally, the individual devices 102 and 103 are integrated by soldering the metal tubing directly to the TO-can, if it is gold plated. Alternatively, the TO-can is mounted to a gold-plated metal tube via thermal curing epoxy, and then soldered to the device 104 that had been mounted inside the gold plated metal tubing.
The opto-electronic integrated fiber optics devices packaged by soldering suffers from several issues. In addition to the issues of the thermal instability and manufacturing difficulty, the soldering process is not an environmental-safe process. The industry is calling on all fiber optical communication components to be environmental-safe by 2007, there is a great need for alternative packaging of optics devices that are amenable to small footprint, broad operating wavelength range, enhanced impact performance, lower cost, easier manufacturing process and environmental-safe.